He encircled the edge of his head

He made a haircut of his hair in a round shape surrounding the head (see Rashi's commentary here).

("You shall not cut the corners of your head, nor shall you mar the corners of your beard" - and he read 19:27, and so on: "You shall not cut the corners of your head - this is the portion of his hair that extends behind his ears and to his forehead, and the circumference of his head is found to be a round calf, with the roots of his hair above the back of his ears and above his many folds" - Rashdi"i and he read 19:27, and so on: "If you circumcise the corners of your head The one who is planted and the one who corrupts his beard, which was this, is also one of the ways of the rebels of Akkum" - Abarbanel and he read 18:23)

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